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Dissertations / Theses on the topic 'Laterality'
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Vainio, Lari. "Affordance, attention and laterality." Thesis, University of Plymouth, 2004. http://hdl.handle.net/10026.1/1915.
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This thesis examines object-guided actions. Recently, micro-affordance effects have shown that a visual object affords actions automatically. These effects are observed when the grasp type (precision and power grasp) is facilitated by size (small and large) of the categorized object (the object-size effect), or when right or left hand responses are facilitated by object orientation (the object-orientation effect). It has been shown elsewhere that attentional mechanisms have a vital role in visually guided movements. In addition, visually guided movements have associated with hemispheric lateralization. Thus, the central focus of the thesis was the role of different components of attention (location-based-, object-based-, endogenous-, exogenous-, focused attention) in micro-affordance effects, and the hemispheric lateralisation of these effects. Using the stimulus-response compatibility (SRC) paradigm, a set of nine experiments (six that employed the object-orientation effect and three that employed the object-size effect) investigated aspects of attention and lateralization in visuomotor integration. A participant performed bi-manual keypresses or precision/power grip responses according to the identity of a target that was displayed over the task-irrelevant prime. Size or orientation properties of the prime object were manipulated, and outcome of interest was how those object properties effected corresponding or non-corresponding responses. The data showed that both micro-affordance effects could be observed when the allocation of endogenous attention to the prime is minimal or absent. However, the generation of both effects were observed to need resources of focused attention. In addition, the data supported the view that the object-orientation effect is generated by the orientation of the entire object and not by a shift of attention to the object’s handle location. Finally, manual asymmetries in these effects suggested that visually guided precision grips are computed predominantly in the left hemisphere whereas power grips are computed in the right hemisphere.
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Ryan-Morgan, T. H. "Handedness, language and cerebral laterality." Thesis, Swansea University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638732.
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This thesis concerns itself with the study of lateral preference and performance behaviours for the functions of handedness and language. The research reported in this thesis addresses the measure and expression of handedness, in the light of current theory and practice; it explores the possibility of differences between left and right handers; it discusses evidence for the existence of a functional relationship between handedness and language; it reports on the expression of language processes within a normal subject population and it reviews the application and interpretations of commonly used methodologies. The results of experiments reported in this body of research are placed within the theoretical framework which has been constructed, in the literature, for the purpose of understanding human cerebral laterality.
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Horn, Barry L. (Barry Lee). "Cerebral Laterality and Leadership Assessment." Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc277963/.
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The major purpose of this study was to determine whether a relationship exists between cerebral laterality dominance and leadership behavior and traits. An additional purpose was to determine whether a relationship exists between cerebral laterality dominance and gender, ethnicity, and educational position.
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Medland, Sarah. "The genetic epidemiology of behavioural laterality /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19204.pdf.
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Ferron, Lucas. "Corticospinal Facilitation During Hand Laterality Judgments?" Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/37010.
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Observing others performing actions is a common way to learn new motor skills. Such ability appears to be linked with one’s ability to imagine actions (motor imagery) (Wang et al. 2014). While motor imagery has been widely used in the context of athletic performance, the same approach has also been advocated in rehabilitation settings, where they often target populations with chronic pain using mobile health applications (de la Vega and Miro 2014). However, we still have very limited information as to how the ability to perform motor imagery addresses this rehabilitation application (Johnson et al. 2012). In the present study, we examined this question by looking at modulation in corticospinal excitability in the context of a motor imagery task. The imagery task itself consisted of judging whether images depicting hands in different postures represented either right or left hands. Based on prior neuroimaging and chronometric studies, such laterality judgments about hand postures are thought to involve mental rotations of one’s own hand (i.e., a form of implicit motor imagery) and thus provided an ideal context to evaluate if advocating such strategy is a valid approach to elicit motor activation in rehabilitation patients (Butson et al. 2014; Goble and Brown 2008; Parsons 1987). To this end, we used non-invasive transcranial magnetic stimulation (TMS) to probe the excitability of the motor system while young healthy participants performed mental rotations in the hand judgment task. Corticospinal excitability was tested in both hemispheres separately (target muscle: first dorsal interosseous) with participants (n=18) seated in front of a computer screen while they performed hand laterality judgments using a commercial set of pictures depicting bare hands in different postures. Excitability was tested also under two other conditions to contrast with variations measured during the hand laterality task, i.e. a mental counting task and a control task (looking at the image of a static foot). In all conditions, TMS (110% resting motor threshold) was set to trigger at ~half of the mean response time in the hand laterality task measured prior to testing with TMS. Comparison of task-related variations in MEP amplitude revealed no significant hemispheric main effect or interaction, although MEPs tended to be larger in general in response to left TMS. A “task condition” effect was observed owing to the large MEP facilitation elicited during the mental counting task, which was significantly different (p<0.001) from either the control “Foot” task or the hand rotation task. In fact, the latter task tended to be associated with MEP depression. A secondary experiment involving a subset of participants (n=6) to examine the influence of image contents (i.e. hand performing actions instead of bare hands) and probing more proximal muscles produced similar results as the main experiment. These results indicate that the general assumption that laterality tasks involving body parts will lead to internal mental rotation and motor activation and enhanced excitability is not necessarily true. In fact, our observations suggest that participants may rely on non-motor strategies based on visual cues when making laterality judgments about body parts. As well, no evidence for hemispheric asymmetry was found with the hand laterality task which is in line with other recent reports. Collectively, these results highlight the need to exert caution when using laterality tasks for rehabilitation purposes. One cannot simply assume that such tasks will translate into motor simulation and facilitation of the motor system. More research should be undertaken before recommending the hand mental rotation task as a viable rehabilitation option for chronic pain.
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Manning, Margaret. "Laterality, reading and ability in children." Thesis, University of Leicester, 1990. http://hdl.handle.net/2381/34667.
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Various hypotheses derived from Annett's (1972; 1985) genetic theory of handedness are experimentally tested. Results from the first investigation show that excessive bias in favour of right handedness is due to a weakness in left rather than superiority of right hand skill, and is associated with poor nonverbal reasoning ability. A second investigation indicated that risks to reading problems were increased in children with either too little or too much bias in favour of dextrality. A further three studies investigated patterns of ability and disability at both laterality extremes. It was found that language deficits were more frequent in children reduced in bias towards the right hand. An attempt to find a task which those at the dextral tail of the laterality distribution were worse at than those at the sinistral tail met with inconclusive results. The experimental findings are, in general compatible with Annett's hypothesis of a human balanced polymorphism with heterozygote advantage for ability.
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Domellöf, Erik. "Development of functional asymmetries in young infants : a sensory-motor approach /." Umeå : Department of Psychology, Umeå University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-751.
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Urbanczyk, Sally Ann. "The Effects of Lateralization of Task on the Use of the Dual Task Paradigm as a Measure of General Intelligence." Thesis, North Texas State University, 1985. https://digital.library.unt.edu/ark:/67531/metadc500501/.
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Stankov's work on attention and intelligence suggests that the dual task paradigm, requiring the division of attention, is a better measure of general intellectual ability than the single task paradigm which does not make this demand. Sixty right handed undergraduates remembered digit and visual-spatial sequences alone and in two dual task conditions involving lateralized key tapping as the primary task. R gher intercorrelations were found under dual task conditions in which the tasks competed for the same hemisphere's resources. Better memory performance resulted when both tasks were lateralized to the same hemisphere. Hierarchical models combining general attention resources with ,lateralized hemispheric resources best account for these resutsi
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Bruckert, Lisa. "Is language laterality related to language abilities?" Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:05e80d0d-8d0b-4cb2-8f94-22763603fab5.
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It is well known that language processing depends on specialized areas in the left side of the brain in the majority of the population. A popular view is that developmental language disorders result from a poorly lateralized brain, but evidence in support of this has been weak and inconsistent. In this thesis, I investigated language-related asymmetries in brain structure and function, and their behavioural relevance in both individuals with specific language impairment (SLI) and typically developing adults. Combining different brain imaging techniques, I looked at group-level as well as individual estimates of language laterality and its relationship to language abilities. The aim of my first two studies was to investigate the neural underpinnings of SLI in terms of white matter microstructure and functional organization associated with auditory processing. For this, diffusion and functional MRI data was obtained in a small number of families with a history of SLI and in control families. Compared with neurotypical controls, children with SLI had lower white matter integrity in the corpus callosum, and in white matter areas corresponding to the dorsal and ventral language pathways. The expected functional lateralization for auditory processing was not observed in either group. In the second half of my thesis, I assessed language laterality in 215 neurotypical adults. I demonstrated that functional transcranial Doppler (FTCD) ultrasonography could reliably assess functional lateralization across different language processes. From this large group, I identified 16 individuals with atypical language lateralization and compared them to a group of 16 typically lateralized individuals using a combination of FTCD, MRI and behavioural measures of language laterality and language abilities. The two groups differed significantly in terms of lateralization assessed by functional MRI and diffusion imaging. The atypical group had lower left and greater right hemisphere activation compared with the typical group, and lacked the leftwards asymmetry in the ventral language tract seen in the typical group. The groups did not differ in terms of cognitive measures. Different functional laterality assessments were concordant in the typically lateralized individuals but were inconsistent in the individuals assessed as atypical by FTCD. In brief, my findings suggest that for some individuals language lateralization may be unstable and varies depending on task or other factors. Even so, such differences do not appear to have consequences for language or other cognitive development.
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Wendt, Peter E. "Variations in functional lateralization." Lund : University of Lund, 1998. http://books.google.com/books?id=5vFqAAAAMAAJ.
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Collinson, Simon Lowes. "Studies of cerebral laterality in early onset schizophrenia." Thesis, University of Oxford, 2001. http://ora.ox.ac.uk/objects/uuid:c1e832af-5a0b-4f72-89af-9f4a295246a2.
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Accumulating evidence suggests that schizophrenia is associated with altered cerebral laterality secondary to a deviation from normal brain development. A number of findings suggest that age of onset of psychosis and gender may have a significant bearing on the nature and extent of the deviation. In order to examine this, early onset patients (12-19 years of age) were compared to healthy controls and later onset patients in a series of studies using standard neuropsychological techniques, experimental divided visual field (DVF) measures and magnetic resonance imaging (MRI). Specific attention was directed to examining the influence of sex and age of onset on hemispheric specialisation. In the neuropsychological studies, early onset patients (n=35) demonstrated significant impairment of intellectual functioning relative to normal adolescents (n=35) but no significant VIQ-PIQ discrepancy. Earlier age of onset was significantly correlated with reduced VIQ and FSIQ. Early onset patients showed significant reduction in hand skill, increased incidence of non-right eye preference and crossed hand-eye dominance. In addition, patients demonstrated reduced right ear advantage (REA) in dichotic listening and inability to modulate ear advantage by directing attention. In the DVF experiments, early onset patients (n=20) demonstrated normal lateralisation in phonological word recognition but sexually dimorphic anomalies in lexico-semantic processing relative to normal controls (n=20). Males showed impairment in imageable word recognition whereas females were more impaired in emotional word recognition. In both cases, the observed anomalies implicated a disturbance in the semantic network subserved by left hemisphere ventromedial and superior temporal heteromodal cortex. In MRI investigations, early onset patients (n=33) had smaller cerebral hemispheres and larger lateral ventricles than controls (n=32). Male patients showed reduction of leftward asymmetry in temporal lobe volume and female patients showed reversal of rightward asymmetry. Significant correlations were found between left ventricular brain ratio and reaction time to phonological word processing. Together, the combined results indicate that early onset schizophrenia is associated with a significant but selective alteration of cerebral laterality, that age of onset is likely to be a determinant of this alteration and that, to some extent, these changes are mediated by gender. The results are discussed within the context of neurodevelopmental aetiology.
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Salvadia, Angela M. "Manual laterality in hearing impaired and hearing children." Thesis, Boston University, 1988. https://hdl.handle.net/2144/38098.
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Thesis (M.S.)--Boston UniversityPLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you.
This study was designed to investigate the differences in hand preference and skilled hand movement between hearing impaired and non-hearing impaired children. The subjects were 78 hearing impaired (44 males, 34 females) and 68 normal hearing children (24 males, 44 females). Hand preference was measured through performance of ten tasks requiring hand use. Skilled hand movement was measured by a timed peg displacement task. The preference scores were classified as right and non-right hand preference and the skilled movement task was analyzed for speed of displacement of pegs for preferred and non-preferred hands. The hearing impaired subjects were significantly different from the normal controls in frequency of right hand preference with normal controls showing more frequent right handedness. The degree of deafness was not a significant factor in frequency of right preference in the hearing impaired group. On the peg displacement task, hand was significant, both the hearing impaired and normal control subjects were significantly faster with their right hands. Group approached significance. The unexpected result was that children with the greater degree of hearing loss performed better than those with less hearing impairment.
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Walsh, F. A. E. "The modification of attentional bias to emotion-related words using the unilateral hand contraction method." Thesis, Coventry University, 2015. http://curve.coventry.ac.uk/open/items/c33984e5-b2da-4565-b2ce-4dcc9e840ff4/1.
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Substantial evidence shows that attentional bias towards threat plays a fundamental role in anxiety and that deficits in frontal brain functioning might explain this. However, a paucity of research on anger related attentional bias leaves unanswered questions about whether similar mechanisms underpin aggression. This has led to a lack of theoretical explanations for anger related attentional bias and effective interventions to reduce anger. Electroencephalographic (EEG) evidence suggests that the hemispheric specialisation of the frontal brain predicts differential responding to emotional stimuli in anger and anxiety. Manipulating motivational direction, via unilateral hand contractions (UHCs), provides a means to explore the causal relationship between anger and attentional bias to threat. Previously, this method has only been used to change experiential and expressional aspects of emotion and its effectiveness in modulating attentional components of emotion regulation are unknown. Therefore, this Thesis aims to explore whether UHCs effectively modulate attentional bias to threat in relation to, and independent of trait anger. It also aims to discover the underlying neural effects of the UHC method to examine whether threat-related attentional changes reflect modulations in cognitive control and/or approach motivation. Finally, this Thesis aims to bridge the gap between the attentional bias and frontal brain asymmetry literature. These aims will be addressed by employing Emotional Stroop and Dot Probe paradigms as well as event related potentials measures. The findings provide evidence that UHCs provides an effective technique to modulate attentional bias to threat. Specifically, RHCs reduce attentional bias to threat independent of trait anger and in individuals with low trait anger but they do not modify attentional bias to threat in high anger individuals. In contrast, LHCs increase attentional bias to threat and this reduced task relevant processing, independent of trait anger. The implications of these novel findings and future directions of research are discussed.
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Dockery, Michael Anthony. "Aspects of laterality in two species of noctuid moths." Thesis, Manchester Metropolitan University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396628.
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Björn, Martin. "Laterality Classification of X-Ray Images : Using Deep Learning." Thesis, Linköpings universitet, Datorseende, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-178409.
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When radiologists examine X-rays, it is crucial that they are aware of the laterality of the examined body part. The laterality refers to which side of the body that is considered, e.g. Left and Right. The consequences of a mistake based on information regarding the incorrect laterality could be disastrous. This thesis aims to address this problem by providing a deep neural network model that classifies X-rays based on their laterality. X-ray images contain markers that are used to indicate the laterality of the image. In this thesis, both a classification model and a detection model have been trained to detect these markers and to identify the laterality. The models have been trained and evaluated on four body parts: knees, feet, hands and shoulders. The images can be divided into three laterality classes: Bilateral, Left and Right. The model proposed in this thesis is a combination of two classification models: one for distinguishing between Bilateral and Unilateral images, and one for classifying Unilateral images as Left or Right. The latter utilizes the confidence of the predictions to categorize some of them as less accurate (Uncertain), which includes images where the marker is not visible or very hard to identify. The model was able to correctly distinguish Bilateral from Unilateral with an accuracy of 100.0 %. For the Unilateral images, 5.00 % were categorized as Uncertain and for the remaining images, 99.99 % of those were classified correctly as Left or Right.
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Boudreau, Vanessa G. "The effects of attention on language laterality in schizophrenia /." Burnaby B.C. : Simon Fraser University, 2005. http://ir.lib.sfu.ca/handle/1892/2107.
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Moore, Benjamin. "Laterality and perceptual-motor skills in elite Australian Football." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/18732.
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This thesis is a study of how within-individual and between-individual lateral preference affects the performance of perceptual-motor skills in Australian football (AF). Results in study 1 demonstrated that whereas AF players executed handballs using both their preferred and non-preferred side during professional games, kicks were performed by predominantly using the preferred side. Study 2 found that when sport-specific hand preference was considered, there were more mixed-hand preference players in the AF population compared to the expert basketball players, with a smaller proportion of mixed-footed and a higher proportion of right-footed players in AF compared to soccer. Study 3 demonstrated that participants were less accurate and had slower RTs when identifying the kicking foot of opposing team players, relative to their speed and accuracy at identifying teammates. Significantly lower discrimination accuracy was also evident in participants’ capability to identify left-footed opponents. Using a ‘snap-kick’ for goal, study 4 found that accuracy was greater with the preferred than the non-preferred foot and greater for easy than difficult kick angles, but there were no accuracy differences due to player footedness. In study 5.1, a set shot goal-kicking task revealed that left-footed AF players were more accurate than right-footed players from a more acute angle relative to the goal. Results in study 5.2 showed that the accuracy cost of ‘look away’ handball passes with the preferred hand was lower for left-handers compared to right-handers. Study 5.3 found reaction time to be faster when players used the preferred hand for handballing. Together, this series of studies indicated that AF skills on the non-preferred side were less developed than the preferred side, although player beliefs and patterns of handedness in games support a more dynamic view of laterality, potentially arising from evolution of the AF competition’s rules and team strategies.
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Jirsová, Adéla. "Úloha laterality mozku v agonistickém chování jelena evropského II." Master's thesis, Česká zemědělská univerzita v Praze, 2016. http://www.nusl.cz/ntk/nusl-256635.
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The theoretical part of this diploma thesis deals with the role of brain laterality of red deer (Cervus elaphus) in agonistic behaviour. Therefore, the largest part of the review of published scientific outcome is devoted to the agonistic behaviour, namely it focuses on the fights between males during the autumn rut. Battles are strictly ritualized and males adhere to strict rules. The role of laterality in animals is being recently studied and the outcomes so far indicates that, particularly in agonistic interactions the laterality may play a significant role. Brain lateralization is simply a preference for one or the other hemisphere in certain activities. The main topic of this thesis is how laterality affects combat of red deer.
The research part took place in a deer-park Zátoň where the duels between stags in rut were recorded. We also used videos from farms Podlesko and Žalany and a deer-park Milešov. These records were processed in the program Noldus Observes, with emphasis placed on the facts which deer was the initiator of the fight and his position to opponent, or with which eye the opponent was perceived at the beginning, but also during the fight. Data were statistically evaluated in SAS software (version 9.4., SAS Institute Inc.). We observed a strong tendency that the winner also initiates the interaction. Chance, that the winner will be the initiator, was compared to recipient 15 times higher. Initiator estimates his option in the battle to win, so he does not let the duel quit before it comes to physical confrontation. Regardless of the character of the behaviour initiator approached his rival more likely on right eye. There was statistically significant demonstrated initiator access to the recipient from the right side in parallel walk as well as in direct physical engagement. As stags train fights during the whole year, so even in the rut are information processed by the left hemisphere, which controls the routine affairs. We can say, that the deer fights during the rut are so frequent, when applies the routine of using antlers as a weapons and therefore we observe right side preference.
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Prieur, Jacques. "Chimpanzees' and gorillas' intraspecific gestural laterality : a multifactorial investigation." Thesis, Rennes 1, 2015. http://www.theses.fr/2015REN1S056/document.
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Nous avons étudié la latéralité gestuelle intraspécifique de chimpanzés et de gorilles captifs dans des contextes socio-écologiques proches des conditions naturelles de vie. Nous avons montré que les chimpanzés et les gorilles étudiés présentaient un biais populationnel pour la main droite pour la majorité des gestes les plus fréquents de leur répertoire. Par la mise en oeuvre d’une approche multifactorielle, nous avons montré pour la première fois que la latéralité gestuelle intraspécifique de ces primates était influencée par plusieurs facteurs et par leurs interactions: contexte de l’interaction (champs visuels de l’émetteur et du récepteur et contexte émotionnel), caractéristique du geste (modalité sensorielle, utilisation d'un outil de communication, degré de partage et durée du geste) et par certaines composantes sociodémographiques, particulièrement le rang hiérarchique de l’émetteur et son âge dans une moindre mesure. De plus, nous avons comparé la latéralité manuelle des chimpanzés lors de l'utilisation d'outil pour des actions non-communicatives et des gestes intraspécifiques. Notre analyse multifactorielle suggère que l’utilisation d’outil dans les gestes serait plus contrôlée par l'hémisphère cérébral gauche que l’utilisation d’outil dans des actions non-communicatives. Globalement, nos résultats vérifient le modèle de Ghirlanda et collègues (2009) selon lequel les biais de latéralité au niveau populationnel pourraient être expliqués par une stratégie évolutive stable basée sur les interactions intraspécifiques. Nos résultats sont également en accord avec les études mettant en évidence l'utilisation préférentielle de la main droite pour la communication gestuelle des primates non humains et suggérant que la latéralité gestuelle serait un précurseur de la spécialisation hémisphérique gauche pour le langage. En outre, nos résultats confortent l'hypothèse que certaines espèces de primates pourraient avoir un traitement spécifique de l’hémisphère gauche pour les gestes communicatifs distinct de celui des actions manuelles non-communicatives. Du point de l’évolution, nos résultats soulignent l’importance d’étudier en détail la latéralité intraspécifique en considérant des espèces de différents degrés de socialité et en prenant en compte des contextes socioécologiques proches des conditions naturelles ainsi que de multiples facteurs potentiellement influentsWe studied intraspecific gestural laterality of captive chimpanzees and gorillas in real-life social-ecological relevant contexts. We evidenced that chimpanzees (respectively gorillas) exhibited a right-hand bias at the population level for the majority of the most frequent gestures of their specific natural communication repertoire. By designing and applying a multifactorial approach, we showed for the first time that intraspecific gestural laterality of primates was influenced by several factors and their mutual intertwinement: interactional context (visual fields of both signaller and recipient as well as emotional context), gesture characteristic (sensory modality, use of a communication tool, sharing degree, and gesture duration) and by some socio-demographic components in particular signaller’s hierarchical rank, and to a lesser extent signaller’s age. Similarities but also some discrepancies between chimpanzees and gorillas may be related to the lateralization of emotional processing, to communication strategies, and to social selection pressures related to the social structure and dynamics of the study species. Moreover, we compared manual laterality of tool use by chimpanzees in both non-communication actions and intraspecific gestures. Our multifactorial analysis showed that tool-use in gestures appear to be governed more by the left cerebral hemisphere than tool-use in non-communication actions. Our findings support Ghirlanda and colleagues’ (2009) model postulating that population-level bias could be explained by an evolutionary stable strategy based on intraspecific interactions. Our results also agree with previous reports evidencing predominant right-hand use by nonhuman primates for gestural communication and suggesting that gestural laterality would be a precursor of the left-brain specialization for language. Furthermore, our results support the hypothesis that some primate species may have a specific left-cerebral system processing gestures distinct from the cerebral system processing non-communication manual actions. From an evolutionary point of view, our findings emphasize the importance to study intraspecific laterality in detail by considering species varying in their degree of sociality and taking into account real-life social-ecological contexts and multiple potentially influential factors
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McKeen, Nancy A. "The meaning of motor activity, emotion, temperament, mood, and laterality." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ51656.pdf.
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Takeuchi, Yuichi. "Dynamics of laterality in shrimp-eating cichlids in Lake Tanganyika." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/136929.
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Jackson, Natalie. "Small set enumeration: the subitizing boundary, laterality and sex differences." Thesis, Jackson, Natalie (2000) Small set enumeration: the subitizing boundary, laterality and sex differences. Honours thesis, Murdoch University, 2000. https://researchrepository.murdoch.edu.au/id/eprint/1496/.
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Previously, the ability to subitize (i.e. to immediately quantify a small set of items without counting) was thought to occur for sets of up to seven items and was explained using a developmental canonical pattern recognition approach. Unfortunately, this approach was unable to account for the ability to subitize linear or random arrays of items, thereby, inspiring a pattern learning and recognition (through stimulus repetition and systematic variation of a base pattern) approach. The latter approach, however, suggests that subitizing is not an independent psychological process and simply occurs as the result of pattern recognition. Contrary to this view, a recent study by Dehaene and Cohen (1994), employing a condition that did not introduce a pattern recognition confound and using a simultanagnosic patient sample, provided sound evidence to suggest that subitizing is, in fact, a separable psychological process. In addition, and importantly for past research into the localisation of subitizing within the hemispheres (which has usually involved the testing of larger sets), a subitizing boundary of two and possibly three items, much lower than originally expected, was found. Furthermore, and in contrast to previous research, recent evidence from Butterworth (1999), drawn from acalculic patients, has suggested that subitizing is a left hemisphere process. This possibility, in light of possible sex differences in laterality and the previous use of the lack of a right hemisphere advantage to indicate abnormal perceptual asymmetry, suggests some cause for concern. The present study was, thus, carried out in order to determine a subitizing boundary and to investigate the possibility of hemispheric and sex differences in laterality. As such, it provided the first comprehensive investigation into the ability to subitize using randomly generated and presented patterns, and a normal adult sample.
A divided visual field task, involving the enumeration of purely random sets of between 2 and 5 items, randomly presented to the left and right visual fields, was employed. Thirty-two undergraduate psychology students (i.e. 16 male and 16 female subjects) volunteered to participate. Based on Dehaene and Cohen's (1994) results it was hypothesised that the subitizing boundary would occur at two and possibly three items. Furthermore, in line with Butterworth's hypothesis, the present study predicted that subitizing would show a left hemisphere advantage. Finally, based on previous research into performance on nonverbal visual tasks, a female subitizing advantage was expected.
The results supported the first hypothesis, indicating a subitizing boundary of two items, thereby, extending Dehaene and Cohen's (1994) research using a normal sample. The second hypothesis, however, was not supported, with the results indicating a strong right hemisphere advantage for subitizing. Finally, the third hypothesis was not supported, with no sex differences found in the ability to subitize. These findings were considered both in the context of Butterworth's hypothesis and in the formation of number systems within remote hunter-gatherer societies. Future research involving young children and a cross-cultural perspective, were suggested.
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Lucky, Nahid Sultana. "Laterality in cuttlefish in regard to the predator and prey interaction." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/157820.
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Leask, Stuart J. "On the presentation and relevance of laterality : a study of psychosis." Thesis, University of Nottingham, 2003. http://eprints.nottingham.ac.uk/11051/.
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A discussion of concepts of lateralization and handedness is followed by an examination of the three-way relationships between lateralization of brain function, level of function, and schizophrenia. It is proposed that conventional examinations of such relationships, using lateralization indices, can be unenlightening or even misleading, and that alternative approaches are preferable. Support for this thesis is sought in analyses of data from two UK national birth cohorts. The author's process of gathering data on psychiatric outcomes is presented in detail. Previously-published findings in this data, employing laterality indices, are presented and their shortcomings discussed. Several alternative approaches to examining the relationships between measures of functional lateralization and level of function are developed, including a novel application of the method of principal curves, and a three-dimensional presentation of function as height over a 'laterality surface'. This latter approach is applied to a number of measures of function in the cohort datasets, including measures of cognitive ability, social success and psychiatric illness, including schizophrenia. The benefits of this method of presentation over previously-published presentations are discussed in the context of several contemporary hypotheses that touch upon the relationships between functional lateralization, cognitive function and schizophrenia.
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Choudhary, Carolyn J. "Why laterality matters in trauma : sinister aspects of memory and emotion." Thesis, University of Stirling, 2008. http://hdl.handle.net/1893/1225.
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This thesis presents an eclectic mix of studies which consider laterality in the context of previous findings of increased prevalence of Posttraumatic Stress Disorder (PTSD) in male combat veterans with non-consistent right hand preference. Two studies extend these findings not just to civilian populations and women, but to left handers and find that left, rather than mixed, handedness is associated with increased prevalence of PTSD in both general population and clinical samples, and to severity of symptoms in the former. To examine issues relevant to the fear response in healthy populations, a movie excerpt is shown to be theoretically likely to target the emotion of fear and to generate subjective and physiological (skin conductance) responses of fear. The film is used as a laboratory analogue of fear to examine possible differences in left and right handers in memory (for events of the film) and in an emotional Stroop paradigm known to produce a robust and large effect specifically in PTSD. According to predictions based on lateralisation of functions in the brain relevant to the fear response, left handers show a pattern of enhanced memory for visual items and poorer memory for verbal material compared to right handers. Immediately after viewing the film, left handers show an interference effect on the Stroop paradigm to general threat and film words and increased response latency compared to right handers, approaching performance of previously reported clinical samples with PTSD. A novel non-word Stroop task fails to show these effects, consistent both with accounts of interference as language processing effects and compromised verbal processing in PTSD. Unexpected inferior performance of females in memory for the film, contrary to previous literature, may also be amenable to explanations invoking compromised left hemisphere language functions in fear situations. In testing one theory of left handedness as due to increased levels of in utero testosterone, the 2D:4D (second to fourth digit ratio) provides mixed evidence in two samples. A possible association of more female-like digit ratios in males with PTSD is a tentative finding possibly relevant to sex differences in prevalence of PTSD. A critique of existing and inadequate theoretical accounts of handedness concludes the thesis and proposes a modification of the birth stress hypothesis to one specifically considering peri-natal trauma to account for the above findings. This hypothesis remains to be empirically tested.
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Toback, Erna Lee. "Laterality of manual and pedal activity in captive chimpanzees, Pan troglodytes." Thesis, University of Stirling, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311652.
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Symon, Bernard Dennis. "Brain Laterality and Pharmacists' ideal interactive work environment: an empirical investigation." University of the Western Cape, 2017. http://hdl.handle.net/11394/6456.
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Doctor Pharmaceuticae - DpharmThe brain laterality of pharmacists may influence where the pharmacists are best suited to work. Brain laterality refers to the asymmetry of the hemispheres of the brain with regard to specific cognitive functions, such as objectivity and emotion. The left hemisphere functions objectively and rationally, whereas the right hemisphere is subjective and nonrational. Animal behaviour in the literature demonstrated an influence of brain laterality, thus selecting an ideal work environment may also be driven by brain laterality bias. Further support for the research included: amblyopia; hemiplegia; the WADA test. The research question investigated the matching of the brain laterality groups of pharmacists to their ideal work environments. The aims investigated: ear, eye, hand and foot dominance in determining brain laterality; influence of brain laterality and reductionistic variables on job choice; location of emotion generation and job choice. Five objectives investigated these aims: influence of brain laterality alone; influence of brain laterality and reductionistic variables; influence of a new brain laterality determining continuum; Propinquity Principle in achieving data; correctness of the Right Hemisphere Theory (RHT) or the Valence Theory (VT). The RHT suggests that the right hemisphere is dominant in processing all emotion. The VT argues that the left hemisphere is specialised in processing the positive emotions while the right hemisphere is specialised in processing the negative emotions. The resulting Null Hypothesis posits that there is no statistical difference between the different brain laterality groups enabling pharmacists to work competently in any placement. The Alternative Hypothesis was that there is a statistical difference between the brain laterality groups, thus brain laterality can be used to best place pharmacists into ideal placements. Global warming questions in the questionnaire determined positive and negative emotion as well as enthusiasm for global warming problems. In South Africa, probability cluster sampling was applied utilising postal and email methods. In the UK, non-probability purposive sampling was applied utilising four methods: snowballing, email, postal, and convenience sampling. Both countries produced similar results for the same sample size.
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Walters, Robert P. "Frontal Regulation of Blood Glucose Levels as a Function of Hostility." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/35310.
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From a neuropsychological perspective, hostile men have displayed dysregulation of right cerebral systems as evidenced through an exaggerated sympathetic stress response, with cardiovascular reactivity for blood pressure and heart rate. Altered right cerebral functioning, with hostility and anger, has been demonstrated within functional cerebral systems to include auditory (Demaree & Harrison, 1997), visual (Harrison & Gorelczenko, 1990; Herridge, Harrison, Mollet, & Shenal, 2003), somatosensory (Herridge, Harrison, & Demaree, 1997; Rhodes, Harrison, & Demaree, 2002), motor (Demaree, Higgins, Williamson, & Harrison, 2002) and premotor systems (Williamson & Harrison, 2003). Each of these studies has demonstrated cardiovascular reactivity (blood pressure and heart rates measures) concurrently with altered sensory or motor functional correlates of the right hemisphere. However, the neuropsychological mechanisms and functional regulation for the mobilization of glucose have not been examined.Master of Science
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Ransley, Kimbra Louise. "Capacity Limits in Visual Processing Revealed by Spatial Biases." Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/19744.
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Our early visual system extracts fine grained information about our rapidly changing world, yet in certain laboratory conditions, participants fail to report some items that are clearly presented within their field of vision. These failures are likely to occur because later stages of the visual system do not have capacity to process all of the information extracted at the retina. In this thesis, I investigate a particular failure of awareness that occurs when two target letters are briefly presented at the same time in different spatial locations. A clue to the cause of these failures may lie in the spatial pattern of errors that participants make. A recent theory suggests that the consistency in spatial errors across participants may reflect a functional strategy used by the brain to prioritise information at a key processing bottleneck. I investigate this claim, and conduct research to investigate other aspects of the limitation, such as the processing stage at which it occurs, and its implications for visual processing tasks such as reading.
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Yasugi, Masaki. "Fish laterality in the predator-prey interaction: investigation from the ethological viewpoint." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/157823.
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Symon, Bernard Dennis. "A Reductionistic Epistemology utilizing Brain Laterality which Investigates Pharmacists' Ideal Interactive Environment." University of the Western Cape, 2018. http://hdl.handle.net/11394/6487.
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Doctor Pharmaceuticae - DpharmThe brain laterality of pharmacists may influence where the pharmacists are best suited to work. Brain laterality refers to the asymmetry of the hemispheres of the brain with regard to specific cognitive functions, such as objectivity and emotion. The left hemisphere functions objectively and rationally, whereas the right hemisphere is subjective and non-rational. Animal behaviour in the literature demonstrated an influence of brain laterality, thus selecting an ideal work environment may also be driven by brain laterality bias. Further support for the research included: amblyopia; hemiplegia; the WADA test. The research question investigated the matching of the brain laterality groups of pharmacists to their ideal work environments. The aims investigated: ear, eye, hand and foot dominance in determining brain laterality; influence of brain laterality and reductionistic variables on job choice; location of emotion generation and job choice. Five objectives investigated these aims: influence of brain laterality alone; influence of brain laterality and reductionistic variables; influence of a new brain laterality determining continuum; Propinquity Principle in achieving data; correctness of the Right Hemisphere Theory (RHT) or the Valence Theory (VT). The RHT suggests that the right hemisphere is dominant in processing all emotion. The VT argues that the left hemisphere is specialised in processing the positive emotions while the right hemisphere is specialised in processing the negative emotions. The resulting Null Hypothesis posits that there is no statistical difference between the different brain laterality groups enabling pharmacists to work competently in any placement. The Alternative Hypothesis was that there is a statistical difference between the brain laterality groups, thus brain laterality can be used to best place pharmacists into ideal placements.
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Michels, Raenel Ruth. "Effects of postural stability and age on behavioral laterality in squirrel monkeys." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/186072.
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Six young and six aged Squirrel monkeys (Saimiri sciureus) made unimanual food reaches from a posturally stable, solid base platform, a posturally unstable fenced ceiling and an extremely posturally unstable chain link tightrope. Although population level right hand biases were present in the solid base and tightrope testing conditions, the monkeys were best described as consisting of two subpopulations; 9 strongly, consistently dextral subjects and 3 strongly, consistently sinistral subjects. The strength of lateral hand preferences, which were weakly expressed in the solid base condition, intensified during the posturally unstable ceiling and tightrope testing conditions. Right or left turning after a manual response was not affected by handedness of the monkeys or directly affected by manual task type. However, young monkeys turn and hand bias directions increased in congruence as manual task stability decreased. Aged subjects showed weak turn and hand bias direction congruence in the posturally stable task and this congruence decreased in the posturally unstable conditions. All monkeys expressed a right turn preference during free movement and this preference was positively correlated to strength of hand biases. Each subject also expressed a left hindlimb preference for mounting and dismounting a chain link fence. However, strongly right handed monkeys showed weakest left hindlimb biases and strongly left handed monkeys showed strongest left hindlimb biases.
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Vordenberg, Jessica. "Laterality Effects in Anterior Stroke: Brixton Spatial Anticipation Test and Functional Outcomes." Xavier University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=xavier1395305623.
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Kwok, Sze-wei. "Functional MRI research on language processing in Chinese children and adults." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B31354932.
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Patston, Lucy. "Balanced brains: an investigation of visuospatial ability and lateralization in musicians." Thesis, University of Auckland, 2007. http://hdl.handle.net/2292/2367.
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Musicians comprise a unique population whereby persistent musical practice involving complex cognitive and motor tasks dates back to childhood when the potential for neural plasticity is at its highest. Accordingly, it has been speculated that musical training results in neural structural and functional differences between musicians and non-musicians. In particular, there is evidence to indicate parietal regions are more equally lateralized in musicians, but research investigating visuospatial abilities and lateralization in musicians is scarce. Studies 1 and 2 aimed to assess the visuospatial ability and cognitive processing speed of adult musicians versus demographically and educationally matched non-musicians. Musicians performed more quickly and more accurately than non-musicians in two tasks of visuospatial ability, and completed more items than non-musicians in three tasks of processing speed, suggesting musicians had better visuospatial ability and a faster speed of processing. Studies 3 and 4 aimed to investigate visuospatial attention in these groups using a line-bisection task and a visual discrimination task. On both tasks musicians demonstrated more balanced visuospatial attention with a slight bias to the right hemispace, which was in contrast to the non-musicians’ bias to the left hemispace, a natural phenomenon known as ‘right pseudoneglect’. In Study 5, the laterality of visual processing in musicians and non-musicians was further investigated by comparing electrophysiological interhemispheric transfer time (IHTT) of lateralized visual stimuli across the corpus callosum. Non-musicians had faster right-to-left than left-to-right IHTT consistent with previous research, whilst musicians had more balanced IHTT in both directions and faster left-to-right transfer than non-musicians. Absolute latency patterns revealed similar results and consistently demonstrated more balanced visual processing in musicians. The behavioural data, analysed in Study 6, revealed a tendency (n.s.) for the musician group to respond more quickly to stimuli presented in the right visual field than to stimuli presented in the left visual field, whilst non-musicians did not show this pattern. Overall, the results indicate that musicians have enhanced visuospatial ability and are less lateralized for visuospatial attention and perception than non-musicians. The results are discussed in relation to plastic developmental changes that may be caused by extended musical training from childhood. Specifically, it is proposed that musical training in early life may elicit a process of myelination that is more bilaterally distributed than myelination in non-musicians.
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Roberts, Candace Freeman. "The relationship between laterality and achievement on a bi-modal learning task in continuing medical education /." Access abstract and link to full text, 1987. http://0-wwwlib.umi.com.library.utulsa.edu/dissertations/fullcit/8712609.
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Hancock, Holly Elizabeth. "Age and functional asymmetry : do lateralized functions decline differentially with age?" Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/28661.
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Mason, Oliver John. "Schizotypy : questionnaire and experimental studies." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318896.
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Brummer, Diana Willig. "A study of the relationship between mixed eye-hand dominance and letter/word reversals in learning disabled and normal males." Virtual Press, 1990. http://liblink.bsu.edu/uhtbin/catkey/720139.
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The purpose of this study was to investigate the relationship between mixed eye-hand dominance and letter/word reversals in learning disabled and normal readers. Previous research had shown links between mixed dominance and reading disabilities, especially those disabilities related to visuo-spatial deficits. However, due to the different approaches to conceptualizing lateral preferences, the wide variety of methods used to assess laterality, and the heterogeneity of subjects exhibiting reading disabilities, many studies have been contradictory and inconclusive. This study was designed to: assess laterality on a continuum, investigate the specific area of mixed eye-hand dominance, and determine if there is a statistically significant relationship between the degree of mixed dominance and the specific reading problem of letter and word reversals.The research sample consisted of 53 learning disabled males and 44 males from regular education classrooms, randomly selected from a public school system in northern Indiana. Mixed eye-hand dominance was assessed by the General Laterality Factor and the Visual Activities Factor of the Lateral Preference Schedule. The degree of letter/word reversal difficulty was-determined by the Jordan Left-Right Reversal Test. Each subject was administered both instruments either individually or in small groups.The data was analyzed for statistical significance by computing Pearson product moment correlation coefficients. To compare the learning disabled readers and normal readers for significant differences in age and the degree of mixed eye-hand dominance, t tests were conducted. Two research questions were then addressed by examining the findings:Research Question #1: Is there a statistically significant relationship between mixed eye-hand dominance and letter/word reversal errors in learning disabled and normal readers? A statistically significant difference was found between the degree of mixed eye-hand dominance and reversal errors in the learning disabled group. No other statistically significant relationships were found.Research Question #2: Is there a greater degree of mixed eye-hand dominance in learning disabled students than in normal readers? There were no statistically significant differences between learning disabled and normal readers in the degree of mixed eye-hand dominance.It was concluded that there were no statistically significant relationships between mixed eye-hand dominance and reversal errors in normal readers or when groups of normal readers and learning disabled students were combined. There was, however, a statistically significant positive relationship between mixed dominance and reversal errors when learning disabled students were grouped separately. The greater the degree of mixed eye-hand dominance, the higher the reversal error score in learning disabled students.Attempts to develop more sensitive and reliable instruments to assess lateral preferences and specific reading problems were recommended. Additionally, studies investigating the relationship between lateral preferences and reading performance should continue.Department of Educational Psychology
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Rice, Grace. "Using neuroimaging and transcranial magnetic stimulation to probe conceptual knowledge in the left and right anterior temporal lobes." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/using-neuroimaging-and-transcranial-magnetic-stimulation-to-probe-conceptual-knowledge-in-the-left-and-right-anterior-temporal-lobes(b834299d-8650-4c7e-89f9-0c503ce64868).html.
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Conceptual knowledge (or semantic knowledge) refers to our shared knowledge for words, objects, people and emotions. The anterior temporal lobes (ATLs) have been identified as a critical region for the representation of conceptual knowledge through convergent evidence from fMRI in healthy participants, cortical electrode implantation and damage-deficit correlations. With the involvement of the ATLs established, recent research has begun to focus on the functions of subregions of the ATLs - with particular interest surrounding the functions of the left and right ATLs. This thesis investigated three main research questions: (1) What are the functions of the left and right ATLs in semantic representation? (2) How does unilateral damage affect the semantic system and what mechanisms underlie the robustness of the system? (3) Do functional gradations exist within the ATLs? These questions were addressed using convergent methodologies including functional neuroimaging and transcranial magnetic stimulation (TMS) in healthy participants and behavioural and neuroimaging investigations in patients who have undergone unilateral ATL resection. To address the question of left vs. right ATL function, this thesis began by directly comparing the predictions of the different accounts of ATL function in a large-scale meta-analysis of the existing neuroimaging literature (Chapter 2) and in a large sample of patients who had undergone unilateral left or right ATL resection (Chapter 3). The overarching finding was that conceptual knowledge is underpinned by a primarily bilateral ATL system, whereby both the left and right ATLs are critical for normal semantic processing. Secondary to this bilateral representation, relative functional gradations were observed both between and within the ATLs. To address the second research question, Chapter 4 investigated the robustness of the semantic system to unilateral damage, specifically regions involved in the maintenance of conceptual knowledge were localised. Results showed that upregulation occurred within regions previously associated with semantic knowledge. The upregulation of activation after unilateral resection also mimicked the upregulation in control participants during more challenging semantic processing. Chapter 5 examined the behavioural relevance of upregulation in the contralateral ATL after unilateral perturbation using a novel TMS protocol in healthy participants. The findings observed here suggest that the bilateral ATL system is resistant to a degree of unilateral damage/perturbation because semantic representations are distributed between the hemispheres. Therefore, unilateral damage/disruption only results in a mild semantic impairment, as the undamaged/unperturbed hemisphere is available to compensate. Finally, Chapter 6 explored functional gradations within the ATLs by comparing responses in the ventral ATL to different conceptual categories, presented as visual and auditory inputs. The functional gradations observed here are proposed to emerge via differential structural and functional connectivity between the ATLs and sensory-motor and limbic cortices.
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Thompson, Naeem Renaud-Phillip. "A Functional Cerebral Systems Approach to Depression: Contributions of the Left and Right Frontal Lobes." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/33575.
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In the majority of the depression literature, there has been little attention paid to the mechanisms underlying the differences that occur among individuals with this label. In a theoretical paper by Shenal, Harrison, and Demaree (2003), they proposed that the differences in depression symptomology may be due to differences in the function (and dysfunction) of the right and left frontal lobes. They go on to explain that each frontal lobe may have a direct influence on patterns of depression symptomology. In the current experiment there was an effort to look at performance differences among depressed and non-depressed males on a tests of affective memory (AAVLT) and functioning for the left (COWAT) and right (RFFT) frontal lobes. Results were non-significant for group based differences but other significant effects were found. Reliable findings included a primacy effect for the recall of words from the negative word list from the AAVLT, whereas t a â normalâ primacy and recency effects were found for the recall of positive and neutral word lists. There were also significant differences (across trials) for both groups suggesting a â normalâ learning curve. It is thought that the non-significant comparisons among the groups are likely due to the qualitatively mild depression scores among participants, which is likely not adequate to capture the level of dysfunction discussed in the original hypothesis.Master of Science
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Faulkner, Deborah. "Asymmetries in unimanual and bimanual coordination : evidence from behavioural and transcranial magnetic stimulation studies." University of Western Australia. School of Psychology, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0048.
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The issue of the laterality of control during unimanual and bimanual coordination was addressed in this thesis. Two tasks were used throughout: a repetitive discrete response task (finger tapping) and a continuous task (circle-drawing). Different mechanisms have been implicated in the temporal control of repetitive discrete movements and continuous movements. The tasks also differ in the degree of spatiotemporal coordination required which might have important implications in the question of laterality of control. The first section of the thesis examined between-hand differences in the dynamics of performance during unimanual and bimanual coordination. During tapping, the dominant hand was faster and less temporally variable than the nondominant hand. During circle drawing the dominant hand was faster, more accurate, less temporally and spatially variable, and produced smoother trajectories than the nondominant hand. During bimanual coordination, several of these asymmetries were attenuated: the rate of movement of the two hands became equivalent (the hands became temporally coupled), the asymmetry in temporal variability during tapping was reduced, and the asymmetry in trajectory smoothness during circle drawing was reduced. The second section of the thesis examined the effects of disrupting motor processes with transcranial magnetic stimulation (TMS) over the left or right primary motor cortex (M1) on the ongoing performance of the hands. In the first study, TMS over left or right M1 during unimanual tapping caused large disruptions to tapping with the contralateral hand but had little effect on the ipsilateral hand. In contrast, for a subset of trials during bimanual tapping, two lateralized effects of stimulation were seen: the effect of TMS on the contralateral hand was greater after stimulation over left M1 than after stimulation over right M1, and prolonged changes in inter-tap interval were observed in the left hand regardless of the side of stimulation. In the second study, TMS over left M1 during circle drawing decreased the accuracy of drawing with both the contralateral and ipsilateral hand, whereas TMS over right M1 decreased accuracy of drawing only with the contralateral hand. This lateralized effect was not limited to the bimanual case, but was also apparent during unimanual drawing. The final chapter addressed issues in bimanual motor control after unilateral stroke. Performance of the affected limb was examined during unimanual and bimanual coordination in a group of stroke patients with varying levels of impairment. The results indicated an improvement in the performance of the affected limb for some patients with mild to moderate, but not severe upper limb motor deficits during bimanual movement. The improvements were limited to the patients who showed evidence of temporal coupling between the hands. These findings support the hypothesis that the dominant motor cortex has a role in the control of both hands during bimanual coordination. In addition, the dominant hemisphere appears to play a role in controlling both hands during unimanual movements which require a greater degree of spatiotemporal coordination. The final study suggests that temporal coupling between the limbs is crucial for the facilitation of performance of the affected limb during bimanual coordination, which has both theoretical and practical implications.
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Broman, Daniel. "Lateralization of human olfaction : cognitive functions and electrophysiology." Doctoral thesis, Umeå : Department of Psychology, Umeå University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-861.
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Demakis, George J. "Functional cerebral asymmetry : a test of the selective activational model /." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-12232009-020403/.
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Spong, Jo-Lene Banita. "Sex differences in brain lateralization for clinically depressed patients." Australasian Digital Thesis Program, 2006. http://adt.lib.swin.edu.au/public/adt-VSWT20070319.125537/index.html.
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Thesis (PhD) - Swinburne University of Technology, Brain Sciences Institute, 2006.Typescript. [A thesis submitted for requirements of the degree of Doctorate of Philosophy, Faculty of Life and Social Sciences, Brain Sciences Institute, Swinburne University of Technology - 2006]. Includes bibliographical references (p. 234-270).
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Mcginley, Jared Joseph. "Lateralized Induction of Cardiovascular Responses: Exploring Asymmetric Autonomic Regulation." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/32888.
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There is clear evidence that the autonomic nervous system (ANS) is lateralized at both the peripheral as well as the central levels of the nervous system. Both the vagus and the sympathetic ganglia asymmetrically innervate the sino-atrial node and the myocardium of the heart. This lateralization has also been observed in afferent as well as efferent projections to nuclei in the brainstem, hypothalamus, and amygdala. Where laterality has not been as clear is in regions of the frontal lobe dedicated to the regulation of autonomic nervous system responses. This study addressed that issue via the implementation of lateralized autonomic response-evoking tasks. With the use of cardiovascular and electrodermal measures, the present study indexed autonomic responses to lateralized stimuli. This study also explored the role of lateralization within sex as well as in relation to reported gender identity. The findings lend support to the right hemisphere as serving a dominant role in regulating sympathetic nervous system activity, while lending less conclusive support for lateralization of parasympathetic nervous system regulation. Men demonstrated greater lateralization for sympathetic nervous system responses across several different metrics of autonomic indices. The exploration of gender variables in relation to lateralization of autonomic responses was generally not supported.Master of Science
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Roberts, Kathrine Ashley. "Laterality effects in processing emotion : a TMS and behavioural investigation of the valence hypothesis." Thesis, University of Hull, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442236.
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Shenal, Brian Vincent. "The Dynamic Cerebral Laterality Effect: Group Differences in Hostility, Cardiovascular Regulation, and Sensory Recognition." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36661.
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This experiment tested two hypotheses linking the right cerebral regulation of hostility and cardiovascular arousal. First, replication of previous research supporting heightened cardiovascular (systolic blood pressure, diastolic blood pressure, and heart rate) reactivity among high hostile participants was attempted. Second, dynamic variations in functional cerebral asymmetry in response to pain (cold pressor) and emotional linguistic processing was measured. Low- and high-hostile participants were identified using the Cook Medley Hostility Scale (CMHS). All participants completed either the negative affective verbal learning test (Experiment 1) or the cold pressor paradigm (Experiment 2). Cardiovascular measures (SBP, DBP, and HR) were recorded and either dichotic listening procedures (Experiment 1) or tachistoscopic lexical recognition procedures (Experiment 2) were administered before and after the stressor. The primary finding of this research was greater left cerebral activation (decreased cardiovascular reactivity) following the dichotic phoneme listening and the tachistoscopic lexical recognition tasks and greater right cerebral activation following pain (cold pressor) and emotionally linguistic (affective verbal learning) stressors.Master of Science
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Comer, Clinton S. "Cerebral Laterality, Emotion, and Cardiopulmonary Functions: An Investigation of Left and Right CVA Patients." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/56981.
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Stroke, or cerebrovascular accident (CVA), is a prominent cause of long term disability in the United States. It has been evidenced that the outcome of a CVA patient differs as a function of the cerebral hemisphere that is damaged by the stroke, especially in terms of emotional changes. The Right Hemisphere Model of Emotion posits that the right hemisphere is specialized for processing emotional content, regardless of valence. In contrast, the Bi-Hemispheric Model of Emotion posits that each hemisphere has its own emotional specialization. The current experiment tested the competing predictions of the two theoretical perspectives in a mixed sample of left cerebrovascular accident (LCVA) patients and right cerebrovascular accident (RCVA) patients using a Dichotic Listening task and the Affective Auditory Verbal Learning Test (AAVLT). Heart Rate (HR) and Pulse Oxygen Saturation (SpO2) were also recorded as sympathetic measures. It was expected that the predictions of the Bi-Hemispheric Model would be supported. A series of mixed design ANOVAs were used to analyze the data. Results revealed that both groups may have exhibited decreased auditory detection abilities in the ear contralateral to CVA location. Additionally, CVA patients recalled significantly more positive words, than negative or neutral words, and exhibited a significant learning curve. LCVA patients exhibited a recency effect, while RCVA patients exhibited a heightened primacy effect. Findings from HR and SPO2 measures suggested a parasympathetic response to neutral information as well as an impaired sympathetic response to negative information in RCVA patients. Taken together these results lend partial support to the hypotheses drawn from the Bi-Hemispheric Model of Emotion, as evidenced by the diametrically opposite effects in these groups, which appears to reflect opposing cerebral processes.Ph. D.
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D'Ingeo, Serenella. "Laterality, heart rate and EEG as measurements of animal welfare in dogs and horses." Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1B010/document.
Full textAbstract:
Le bien-être animal est considéré un phénomène multidimensionnel basé sur les conditions et les expériences de vie de chaque individu, et lié aux fonctions organiques et à la sensibilité de l’individu même. L’étude des émotions animales est complexe mais les hypothèses sur leurs états émotifs peuvent être formulées sur la base de mesures neurophysiologiques, comportementales et cognitives. Des études récentes ont montré que la latéralité cérébrale et comportementale, la fréquence cardiaque et l'activité cérébrale (mesurée par électroencéphalographie sont des paramètres qui permettent d’évaluer la perception de la valence et du niveau stimulant des émotions chez l’animal et l'Homme. Le but principal de ce projet de thèse était d’étudier la perception que les chiens et les chevaux ont du contenu émotionnel des signaux humains et l’impact potentiel que peuvent avoir ces signaux sur l’état émotionnel de ces animaux et par conséquent sur leur bien-être. Dans ce but, nous avons présenté à ces animaux des stimuli exprimant diverses émotions. Nous avons utilisé une approche intégrée combinant l’analyse de la latéralité comportementale, de la fréquence cardiaque, de l’activité cérébrale et du comportement des sujets afin de répondre à 2 questions: 1) les chiens et les chevaux perçoivent-ils le contenu émotionnel des signaux humains? 2) Les chiens et les chevaux attribuent-ils une valence et une intensité différentes selon les émotions humaines perçues. Les résultats de ce travail de thèse montrent que les chiens et les chevaux traitent différemment les signaux émotionnels en fonction de leur valence et de leur intensité. La perception de la voix de l'homme par le cheval est modulée par la valence des interactions homme-cheval antérieures et par les conditions de vie des chevaux. En ce qui concerne les chiens, nos résultats montrent qu’ils discriminent et perçoivent les émotions contenues dans les signaux visuels, auditifs et olfactifs humains différemment, et nous fournissent de nouvelles connaissances sur le fonctionnement émotionnel du cerveau du chien. Les résultats de ce travail de thèse apportent un cadre théorique pour définir des paramètres utiles à l'évaluation du bien-être animalAnimal welfare is considered to be a multidimensional phenomenon based upon life experiences and conditions, characterized by how an individual feels and functions. The study of emotions in animals is difficult but assumptions of emotional states are usually derived from neurophysiological, behavioral and cognitive measurements. Recent literature shows that cerebral and behavioral laterality, cardiac activity and brain activity (measured by electroencephalography) are suitable parameters to examine animals’ and human emotional processing along the valence and arousal dimensions. The main aim of the present research project was to investigate dogs and horses perception of the emotional content of human signals that potentially affects animals’ affective state and welfare. An integrated approach combining the analysis of behavioral lateralization, cardiac and brain activity, and subjects’ behavior was applied in order to answer to the following questions: 1) Do dogs and horses perceive the different emotional content of human signals? 2) Do dogs and horses attribute a different valence and intensity to the human emotions perceived? Overall, the results of this thesis project demonstrate that dogs and horses process differently emotional signals according to their valence and intensity. In particular, horses perception of a human voice is modulated by the valence of the prior horse-human interactions and by subjects’ living conditions. As for dogs, results demonstrate that they discriminate and perceive differently the emotional content of human visual, auditory and olfactory signals, providing new insights into the emotional functioning of the canine brain. The current research offers a theoretical framework for defining useful parameters to evaluate animal welfare